Collabtive is an open source alternative for proprietary tools like Basecamp or Active Collab.
Here are some key features of "Collabtive":
· Easy to use
· Projects, milestones, taskslists, tasks
· Basecamp import
· Timetracking
· Multilanguage Projects
· File management
· Messages
Requirements:
· PHP 5.1 or later
· MySQL 4 or later
· JS/DOM capable browser (tested on Firefox 2/3, Internet Explorer 7, Opera 9, Konqueror, Safari)
What`s New in This Release: [ read full changelog ]
· Fixed bug when assigning tasks while email notification is deactivated / off
· Added name of the project to the desktop calendar overlay
· Fixed date format in calendar overlay on desktop
· Improved translations: French, Portuguese, Czech, Brasilian Portuguese, Polished
· Modified max no. of users to show on projects, now 10000 instead of 100
· Remove the option "All" from the task edit form on single task view
· Fixed a bug where a folder wouldnt be visible if visible = all was selected
· Fixed a bug where every timetracker entry was tracked for "today" regardless of selection
· Removed some debug output in managefile.php
· Added check for userpermission of file editing, so the edit icon will not show up
· any longer in case of missing permission
· Added missing truncation to project title on the mymessages view
· Corrected file->delete link for attached files in the message view
· Backported never due for projects to the frost theme